For many hearing loss patients, bone conduction hearing aids offer a better solution than more conventional acoustic/air transmitting hearing aids. Indeed, for some patients, bone conduction hearing aids offer the only solution. Bone conduction hearing assistance generally involves vibration of the patient's mastoid bone to improve hearing perception. In a typical bone conduction hearing aid, sound sensed by a microphone is converted to an electrical signal and amplified. The amplified signal is then received by a small vibrator which vibrates the mastoid bone.
Strategic placement of the vibrator on the user is essential in order to achieve optimal results. For example, some bone conduction hearing aids teach that the vibrator should be placed against the skin behind the ear, while others teach placing the vibrator on the forehead. Still others teach surgical implantation of the vibrator directly into the mastoid bone for better transmission of vibration. One particularly effective approach has been to mount the vibrator on an ITE structural member. The structural member is inserted in the patient's ear canal so that the vibrator is positioned adjacent the mastoid bone.
In prior hearing aids, a relatively stiff electrical cable connected the ITE component containing the vibrator to a BTE component containing a microphone and processing electronics. The stiff interconnecting cable of prior units provided a pathway for vibrations from the vibrator to the microphone. These vibrations caused undesired feedback or “ringing” which is irritating to the patient.
What is needed, therefore, is an apparatus that reduces mechanical feedback between the ITE component and the BTE component of a hearing aid device.